Time stability of dye-sensitized solar cell based on ZnO sphere aggregates

► Time stability of ZnO sphere aggregate DSCs sensitized by N719 is systematically investigated. ► About 90% of the initial energy conversion efficiency is found after half a year running. ► The decrease of efficiency only happens in the first week. ► The decrease of conversion efficiency attributes to a small drop of short circuit in the first week. ► The FFs of the cells are constant in the whole duration.